Refining of zinc.



G. C. FHCKER.

REHNING or zmc.

APPLICATION FILED lAN.27, 1917. @92879949 Patented Dec. 17, 1918.

3 SHEETS-SHEET l.

G. C. FRICKER.

REFINING 0F ZINC.

APPLICATION FILED JAN.27.1917.

Patented Decl 17, 1918.

3 SHEETS-SHEET 2V G. C. FRICKER.

REFiNING 0F ZINC.

APPLICATION FILED IAII.21. IQII.

Patented '1160. 17, 1918.

3 SHEETS-SHEET 3.

FICE.

GUY CAREY FBICKEE, OF LUTON, ENGL.

BEFINING vOF ZINC.

Specification of Letters Patent.

Patented Dec. 17, 1918.

Application le January 27, 1917. Serial No. 144,976.

To all whom t may concern.'

Be it known that I, GUY CAREY FRICKER, a subject of the Kin of GreatBritain and Ireland residing at uton, in the county of Bedfor England,have invented Improvements in or Relating to the Refining of Zinc, ofwhich the following is a specification.

This invention has reference toA improvements in the refining of zinc bythe distillation method whereby high grade" zinc can be produced frominferior grades of zinc. It also has reference to improvements in zincdistillation and condensmg plant suitable for carrying out the improvedmethod of refining zinc. A

Accordm thereto for obtaining high grade zinc from impure grades ofzinc, the zinc vapor that is being distilled off from a melted charge ofimpure zinc is caused to pass through a filter composed of inertrefractor material composed for example of dry oundry coke or otherequivalent porous or absorbent material that will act to absorb andretain impurities mixed with the zinc vapor, so that the zinc vaporpassing from the filter will be in a purified condition. The filteringmaterial may be broken up into pieces of about one cubic inch capacityand shoveled on to the top of the charge of molten impure zinc in acrucible or other vessel -so as to form thereon a fioating layer of sayabout three inches in thickness, the Crucible being made sufficientlydeep for the purpose. The filter is removed after the treatment of eachcharge. The impure metal left at the bottom of the crucible can beremoved at intervals, say about once a week, or once a fortnight in thecase of a Crucible adapted to contain a charge of about fivehundredweight.

In order to admit of the distilled zinc being condensed in anadvantageous manner and so that the production of blue powder zinc,which is undesirable, shall be diminished as far as possible, thecondensingI vessel, or each such vessel, preferably in the form of aCrucible, is maintained at a temperature a little. above the meltingpoint of the zinc so that the zmc can be collected in the liquid stateand run off into molds. For thus heating the condensing Crucible, thechamber therefor may be separated from the heating chamber containingthe distilling Crucible by a wall having a connecting opening throughwhich hot gases can pass from the latter to the former chamber under thecontrol of a. closing device.

The accompanying illustrative drawings show distilling and condensinglant accordlng to the invention and sultable for carrylng out the zincrefining method above described.

In the drawings, Figure l is a vertical sectlon on the line A A of Fig.2 and Fig. 2 a plan of the said plant. Fig. 3 shows the plant partly infront end elevation and partly in cross section on the line B B of Fig.2. l F1g.4 is a plan of a re grate and F1g..5 1s a cross section thereofon-the line C C. of Fig. Il.

In the example shown the plant comprises a heating and distillingChamber a and a cooling or condensing Chamber b arranged slde by slde tocontain the distilling and condensing crucibles c and d respectively andseparated from each other by a vertical wall e.

f Flg. 3) shows the thick layer of porous lterlng material such ashereinbefore referred to arranged above and so as to ioat on andCompletely cover the molten charge f1 of unrefined zinc in one of thecrucibles.

The Vertical wall e is provided at or near the fioor of the cooling orcondensing chamber b with one or more horizontal connecting passages gadapted to be closed to a greater or less extent by one or more brickslz for controlling the passage of hot gases from the heating anddistilling chamber (hereinafter called the distilling chamber) to thecoolin or condensing chamber (hereinafter calle the condensingcompartment). The distilling Chamber a is constructed with two fireboxes z' separated by a vertical dividing wall c. This wall is adaptedto su port, preferably by a couple of lateral y v as shown, bytransverse walls 'a into a number of independent condensing chambers beach containlng a Condenslng Crucible d. Each fire box z 1s providedwith a fire door o and with a hearth preferably consisting of a castiron plate p formed with a number of conical openings fr therethrough,(Figs. 4 and 5) the smaller ends of the holes being at the top. Thisfacilitates the removal of clinlrer. rlhe ash pit e below each grate isclosed and provided with a pipe t for the admission of air underpressure. The distilling chamber a is covered by a roof u of refractorymaterial made in parts that surround the upper portions of thedistilling crucibles c and are supported by ledges v on the side wallsof the heating chamber e and by central vertical supports or pillars wcarried by the wall c, these supports or pillars being so arranged, asshown, as to admit of flame and hot gases from the fire boxes i passingfreely around the crucibles c. rlhe rear end of the distilling chamber acommunicates with a chimney or flue rlhe condensing chambers b havetheir floors preferably at a level corresponding substantially with theupper surfaces of the supporting bricks m for the distilling crucibles aand upon them rest the condensing crucibles Z which are preferablysimilar to the distilling crucibles a except that each of them isprovided at the bottom with a tapping hole g/ normally stopped by loamor red sand, a gutter e being placed below each tapping hole, rlhedistilling crucibles c are preferably ordinary plumbago .crucibles rlhecondensing crucibles (Z may be of similar material, or of clay, orconsist of clay lined iron vessels. Both sets of crucibles are providedwith covers l and 2 respectively that are luted in place and connectedtogether in pairs by pipes or tubes 3 of clay, plumbago or equivalentmaterial that will not affect the purity of the zinc vapor passingthrough them. rllhe covers l of the distilling crucibles c are eachprovided with an aperture l at the top that is closed only after gaseousproducts from the heated filter floating on the molten charge of impurezinc in the crucible, and any air initially contained in the Cruciblehave been discharged. This point is readily determined by escaping zincvapor burning freely at the aperture with its characteristic flame. Whenthis 0ccprs, the aperture is stopped by a plug of c ay.

rlhe crucibles c and Z may each be covered by a hood, as indicated indotted lines at 5 in Fig. l, that is adapted to retard loss of heat fromthe top thereof.

The side and end walls of the distilling and condensing chambers aresupportedy by external pillars 6 and tie rods 7 in the usual manner.

What l claim is l. The method of obtaining high grade zinc from animpure grade of zinc which consists in-causing the zinc vapor` producedby heating a charge of impure zinc to pass incase@ through a filter ofinert material, arranged above, floating upon and coinpletelv coveringthe inolten charge of impure zine so that the Zinc vapor is constrainedto pass upward Wholly through said filter and condensing the resultingpurified zinc vapor.

.2. 'llie method of' obtaining high grade z1nc fioni an impure grade of'zinc which consists in causing the zinc vapor produced by heating acharge of impure zinc to pass through a filter composed of a layer ofpieces of refractory porous or absorbent material floating upon andcompletely covering the molten charge of impure zinc, so that the zincvapor is constrained to pass upward wholly through said filter, andcondensing the resulting purified zine vapor.

.3. l` he method of obtaining high grade zinc'from an impure grade ofzine which consists in causing the zinc vapor produced by heating acharge of impure zinc to pass through a filter composed of pieces ofcoke arranged to form a thick layer floating upon and completelycovering the layer of impure molten zinc Se that the zinc vapor isconstrained to pass upward Wholly through said filter and condensing theresulting zinc vapor.

The herein described method of obtaining high grade zinc from an impuregrade of zinc which consists in placing a charge of the impure zinc in adistilling vessel, completely covering it with a thick layer of piecesof inert refractory material of a porous or absorbent nature that restupon the charge of impure zinc, heating the charge of zinc to thevolatilizing temperature so that the resulting zinc vapor is constrainedto pass through the filter floating 0n the molten charge, whileimpurities present inthe zinc vapor rising from the charge will beremoved therefrom and retained by the filter, and condensing the zincvapor leaving the filter.

5. rlhe method of obtaining high grade zincfrom an impure grade of zincwhich consists in causing the zinc vapor produced by heating a charge ofimpure zinc to pass through a filter of inert material arranged above,floating upon and completely covering the molten charge of impure zincand condensing the resulting purified Zinc vapor at a temperatureslightly above the melting point of the purified zinc.

6. ln zinc distilling and condensing plant, a distilling chamberprovided at its lower part with laterally arranged lire boxes havingbetween them a division wall and at one end with an outlet for hotgases, a longitudinal row of distilling vessels carried by said divisionwall, vertical supports carried by said division wall between thedistillingvessels and a roof of refractory inaterial made in piecescarried partly by the side walls of the distilling chamberl and partlyby the vertical supports and adapted to surround the upper portions ofthe distilling vessels.

7. Zinc dstilling and condensing plant. comprising separate distillingand condensing vessels, a heating chamber for said distilling vessel,connecting means for zinc vapor between the distlling and condensingvessels and means whereby hot gases from the heating chamber can beutilized to heat 1e the condensingvessel.

Signed at 75/77 Cornhiil, in the city of London, England, this fifth dayof January,

GUY CAREY FRICKER.

' Witnesses:

J. M. DE nn Los Nros, i WM. 0. BRAEnEo.

